Upload
byron-lane
View
213
Download
0
Embed Size (px)
Citation preview
SUMMER INSTI
TUTE
2012
BR
I DG
E &
MA
ZE
DE
SI G
N
Team Members: (left to right)
Ai Choo AsheShelley CadyLisa BoettcherJim HamblettMartha Harrison
PROBLEM #1: Algebra-in-Action Bridge Design
Construct a bridge using truss design. The span must be greater than or equal to 100 cm.
The Warren Bridge
THE PROCESS: System Analysis• Took inventory of all our supplies; listed the dimensions & number of
beams and joints, and reviewed directions.
• Upon the recommendation of our tech teacher, we decided to build a Warren style truss bridge (strength & stability).
• The art teacher drew 2D and 3D renderings of a Warren bridge to determine if we had enough supplies for our design. She made several drawings before she said, “This is the bridge we can build.”
• Construction was next with a few adaptations to our original picture.
• Force was tested with the instruments provided. This testing brought up new questions (See next slide).
• The word problems and questions came from our experience with the construction and testing of the bridge.
THE PROCESS: System AnalysisFrom the model determine the following:
• What is the height of the truss?
• What is the width of the bridge?
• Find the critical force where bucking occurs and write an inequality
• Use the Pythagorean theorem to verify the right triangles in the truss design.
• With a scale of 1 cm. = 10 m, find the actual dimensions for each beam.
From the span of the bridge, do the following:
• Write an equation to determine the number of beams used for the bottom chord
• Write an equation to determine the number of beams used to find the top chord. This equation must work for any given span.
• Write an equation to determine the number of joints you will need to construct the bridge.
• Why is there a discrepancy in the force when a weight sits on the track versus when it is hung from a horizontal beam? Use percent of change to show the result of this experiment mathematically.
THE PROCESS: The VariablesDiscuss how the pertinent variables that affect the strength of the bridge:
• The load: the more triangles in the design, the stronger the bridge.• Truss height: Will change (a) the hypotenuse• Diagonal (a) the hypotenuse: as the diagonal gets longer, the number of joints
decreases and therefore, the strength of the bridge which will also affect the maximum load.
• Cross section- square, round or I-beam will affect the strength of the bridge: I-beam being the strongest.
• Force (load) to be supported: consider the following..1. What kind of traffic will the bridge need to accommodate? Trucks can
now carry heavier loads2. Environmental issues such as: Is this bridge in an earthquake zone?
• Materials used in construction will affect the strength of the bridge.• F max the maximum weight at failure: a safety factor of 2 is usually applied in
all constructions.
CALCULATIONS:1. 4(.17m)(π2)(2.3x109N/m2)(6.9x10-10m4) / (.24m3) is approximately 770 N
Adjusting for the gravity and safety 770/9.8 x ½
Maximum load is approximately 39 kg
2. l2 + h2 = a2 l2=a2- h2 h2= a2-l2
3. The track becomes another beam and also exerts a force .
4. Proportion: 1 cm = length of the given beam in cm 10m x
Actual height is h=170 meters, and a= 240 meters
5. m= 4 (s/L )-3 21 per side
6. 2j = m+3
j= 2S/L 12 per side
EXTENSION:Cost and profit of the project.
Given values for prices. What is the total cost? Is the Warren bridge the most cost effective for the load it needed to carry? Would another style have been cheaper? Discuss and verify.
REFLECTIONS:Project was valid because:
• Incorporated all our expertise: tech teacher: prior knowledge of bridge construction, art teacher: graphical visualization of bridge design, math teachers: wrote equations and verified numbers
• Activity is relevant and applicable to classroom setting where students of varied talents can work together towards a common goal.
• Activity is relevant for learners who enjoy hands-on manipulations
MAZE PROJECT: System Analysis
Problem:Design a maze in a shipping
terminal
VARIABLESTALWCALc
Wc
CSSLs
Ws
CoSGAGWPWTW
TLTHLUAAATLARTACSARMANc
Ns
TWTLTHUa
EQUATIONSTA= LxWCA= Lc x Wc
CSS = LS x WS 1.25( Lc) x 1.25(Wc)CoS= ns x CA = ns x Ls x Ws
GA= f(fraction) (TLA)RTA= g(TLA)LUA= a% (TA)AA = b% (LUA)RMA= c% (TA)TLA=d%(TA)CSA= e%(TLA)Unit area= ( 65/61Lc + PW) (61/67(Wc) + PW)PA = TA – Ns (Ls x Ws)
INFORMATION: RESOURCES & CONSTRAINTS• Total Area = 2,000,000 ft2
• TEU = 20 x 8 x 8.5• CA = 160 ft2 • LUA = .06 ( 2,000,000) a=6% 120,000• AA= .03 (TA) b=3% 60,000• RMA= 4% (TA) 80,000• CSA= 3% (TA) 60,000• GA= 2%(TA) 40,000• TLA= 12% (TA) 240,000• RTA= 4%(TA) 80,000• 1 Unit = includes the container, slot, and pathway. Size is
944 ft• Pathway has to be 35 ft wide to allow for the length of the
container and lift truck• df= 14 – 11 df = 3
DESIGN A MAZE FOR ROBOTIC LOADING & UNLOADING CONTAINERS
Given resources and constraints: Total Area = 2,000,000 ft2 TEU = 20 x 8 x 8.5 CA = 160 ft2] LUA = .06 ( 2,000,000) a=6% 120,000 AA= .03 (TA) b=3% 60,000 RMA= 4% (TA) 80,000 CSA= 3% (TA) 60,000 GA= 2%(TA) 40,000 TLA= 12% (TA) 240,000 RTA= 4%(TA) 80,000 Pathway has to be 35 ft wide to allow for the length of the container and
lift truck df= 14 – 11 df = 3
MAZE DESIGN PROBLEM
A 2,000,000 ft2 area is available for the construction of a new maritime shipping terminal.
Loading/Unloading area is 6% of Terminal area.
Administration area is 50%
Repair/Maintenance area is 4%
Truck Loading/unloading area is 12%
Chassis storage area is ¼
Gate Area is 1/6
Rail Terminal is about 1/3
Design a maze for robotic loading and unloading containers.
PERTINENT VARIABLES
The size of the pathway was not given as a fixed value. We had to know the amount of space needed by the robot, forklift, etc. in relation our Unit (container, slot, pathway).
This pathway size also affects the number of slots available to store containers. None of this could be calculated until a pathway size was defined.
Most of the terminal related to the TA available for building.
Decisions had to be made about how the pathways were set up to accommodate loading and unloading the containers. Would the robot need to maneuver in between the containers or would some containers touch the fence on one or more sides, etc.
Due to the forklift, the pathway must accommodate the length of the container (20 ft)
WORD PROBLEM:
A 2,000,000 ft2 area is available for the construction of a new maritime shipping terminal. Loading/Unloading area is 6% of Terminal area.Administration area is 50% Repair/Maintenance area is 4%Truck Loading/unloading area is 12%Chassis storage area is ¼ Gate Area is 1/6 Rail Terminal is about 1/3
WORD PROBLEM QUESTIONS1. What area is available for storage containers?
1,320,000 ft2
1,320,000/ 944 = 1398 units can fit in the remaining area designated for storage.
2. Change container length to 40ft, how would this affect the number of containers?
3. How many additional units could be stored if the RTA was reduced by 50%?
4. The storage fee for containers is $12.00 per container and a maintenance fee of $25.00 everyday. You begin with 1400 containers on day 1. If you can ship 350 containers per day, what would your total rental fee be for 4 days? Draw a chart for day 1, 2, 3, and 4.
5. Write as equations first. Given total of 1400 containers, solve for the rental fee.
DELIVERABLES #4
Last problem: What is the maximum capacity of storage for you shipping
terminal?
66% of TA = 1,320,000 ft2 space available for storage and pathways
CoS = ns x Ls x Ws PW A = 1042580 ft2
CoS = 2078 x (65/61)20 x (71/61)8
CoS = 412360 ft2
Our design allowed every two containers in slots to be placed next to each other without a pathway . This increased our number of containers to 2078. Storage Area 1 is 439 ft. x 682 ft. to accommodate 1116 containers. Storage areas B and C measure 200 ft. x 800 ft. each. Each accommodates 481 containers.
REFLECTION
We had a better understanding of the system analysis process for this project. The experience of the first one allowed us to work on this project. We were able to apply more creativity to this project such as the 3D representation of our design. It was rewarding to see the numbers jive with our terminal plan. Our Technology teacher explained the design of the maze as the same as the aisles of a grocery store. This visual and use of prior knowledge gave us a better understanding to our maze problem.
We applied the math to calculate maximum storage capacity and considered the practical applications of unloading and restocking containers at a terminal. Containers come in and go out constantly in the real-life problem.